def find_lowest_leftmost_point(points):
    bottom_left = points[0]
 
    # 遍历所有顶点以找到最左下角顶点
    for vertex in points[1:]:  # 从第二个顶点开始比较
        if vertex[1] < bottom_left[1] or (vertex[1] == bottom_left[1] and vertex[0] < bottom_left[0]):
            bottom_left = vertex
    return bottom_left
 
# 示例使用
vertices = [(5, 7), (2, 3), (4, 1), (1, 2), (3, 6), (1, 3)]
lowest_leftmost = find_lowest_leftmost_point(vertices)
print("最左下角顶点的坐标是:", lowest_leftmost)